The modern connotation of Damascus steel is different from the original Damascus of the past. Historic Damascus steel referred to as crucible stee,l which had a very high carbon content and had a visible surface pattern because of its crystalline structure.Tthis Damascus steel, or Wootz steel, ended up being called Damascus steel because the crusader,s on their way down to the Holy Lan,d would purchase new blades of this superior steel (superior to medieval European steel) in cities like Damascus. The modern connotation, however, is instead different kinds of steels that have been pattern-welded and that display a similar surface pattern when acid etched. The Damascus you will see made here is is of the latter definition. Cable Damascus is perhaps one of the easiest ways to create Damascus steel with a complex pattern. Unlike other techniques, this method requires no folding and essentially comes in its own ready to forge shape.
Step 1: Safety
Like they always say, safety first! Seeing as how this whole process involves forging, grinding and dipping metal into chemicals, it is important to use the proper safety equipment. For the forge welding stage, many people who do any kind of smithing, know the basic safety equipment: gloves, apron, closed toed shoes, etc. Howeve,r one piece of equipment sometimes goes overlooked. Everyone knows that eye protection is important but for this kind of work you need a special kind of eye protection. The above and only picture in this section is of a pair of dydidium glasses. The reason that it is the only picture up there is because just about everybody who works with metal knows the safety basics but rarely do I see people point out this kind of eye protection. Normal goggles are usually fine for most crafts but not for forge welding. The heat required for forge welding puts out a bit of radiation that over the long term can cause vision loss. Dydidium however will block most of the radiation and save your eyes. One final point, dydidium glasses are not the same as welding masks or sunglasses. If you use either of these while forge welding, your pupils will dilate and your eyes will get even more of the radiation.
Step 2: Billet Prep
Before you can forge out your section of cable you have to set it all up. Before it goes in the fire you first have to cut off your section like in the first image. I cut off 3, 12 in sections of 1 inch cable at the time with a chop saw. You can use whatever method you like to cut the cable just be sure that the cable that you use is all steel with no plastic involved and that it is not galvanized as the heat reacting with the plating will produce gas that can make you very sick or even kill you. So keep that in mind when getting cable. Also, if this is your first time attempting cable Damascus you might not want to jump right in to the the larger diameter cable and instead start out with a piece of half inch. You wont be able to make anything more than a toothpick with the results but its a good way to practice without wasting bigger and more expensive cable.
After the cutting, be sure to wrap the ends of the cable with steel wire. This is to keep the section from unwinding during the first parts of the process. Be sure to only use plain steel wire because other wires that are coated or are made of other can melt or react with the heat and just mess everything up.
Everybody who makes Damascus has their own list of steps or additives that seem to make the whole process work for them. I encourage you to go, do some research and discover one that works for you. For me, I spray my cold metal with WD40 until it is just completely soaked and then coat the whole thing with regular borax before putting the sections in the fire. Both the borax and WD40 act to prevent oxidation which can make forge welding impossible. The borax won't typically stick to metal unless its hot or wet and the WD40 will burn off in the forge so getting the section wet with WD40 and using that to stick the borax on seems to make everything work for me.
Step 3: Forge Welding
Once in the forg,e you need to let this piece get hot and I mean high orange to yellow hot. Once it has reached the appropriate colo,r let it sit for another minute or so so that the whole section has soaked up the heat and it is evenly hot.
Before any hitting can be done, the section must first be twisted. Cable is full of empty space and empty space is bad for forge welding. Secure one end of the cable in a vice, or something similar, and use what ever tool you deem appropriate (I used channel locks) to twist the section in the direction that the cable is already twisting. This step may take several re-heatings. Keep twisting the cable until it can no longer be twisted without kinking. Be sure that the cable does not kink as that makes the whole process a bit more difficult.
After every step, until you are sure that the section is one homogeneous piece of steel, you should coat it in borax before placing it back in the fire. Coat the piece when it is a dull red color that will make sure that the borax sticks. One point to make about borax is that when it is hot it is very caustic and can destroy the inside of your forge so be sure that you have a piece of firebrick or something to protect the base of the forge. Also, hot borax coming off the piece in the next step can be rather painful and can leave scars so be sure to wear the appropriate gear. The last part of the forge welding is the actual welding part. Once the piece is hot, you can start hitting it. The idea is to hit it into into a square bar at first. As you hit around the bar, you should follow the twist of the cable. Personally, I prefer to start hitting in the middle and work my way out. Hitting will cause the fibers so separate to some extent so the shorter the distance from the first hit to the end of the hit the less the separation will occur. You will know that the piece is homogeneous based on the change in sound that the piece will make when being hit. Initiall, it will be more of a dull thud with each hit but once homogeneous it will make a bit more of a ping sound. Once it is homogeneous it can be beaten into the preferred shape.
Step 4: Shaping
When planning a projec,t be sure to remember that the final product will be much smaller than the original cable. Also keep in mind that the ends of the cable might fray and not weld. Don't fret. Just find where the weld starts and cut off the end. Because of the nature of cabl,e and the number of gaps and ridges in it you are bound to end up with pits and holes unless using a pneumatic hammer or a forge press. The key is to grind the bar down, see what you are working with and plan around that. I wanted to make pendants from my pieces and I decided that a kite shield would be and interesting shape. The finer the grit that you use when doing the final grind will determine how well you can see the pattern. Since I wanted a very deep etch i didn't need to go too high so i only went about 120 with the grit before the etch.
Step 5: Final Etch and Protection
Damascus steel when ground down should look just like one solid piece of metal. In order to get the pattern, you need to etch the steel with an acid. There are several options as far as acids go but personally I use ferric chloride. If you only want a very superficial etch, like the one in the cover image, you only need to dip the metal in the acid for about 20 min. I wanted a very deep etch that could actually be felt so I dipped mine for 7 hours. Once you are done with the etch, you need to clean it and neutralize the acid. One of the easiest ways to do that is just to spray Windex on the etched piece after it has been rinsed off. Don't forget to wear gloves and eye protection for all this. If you want to add some color to the piece, like the last two images in the title, just heat the piece up a bit after the etch until the desired color has been reached.
Once the etch is done, the last step is to protect the piece.Ssteel is strong but unfortunately has a tendency to rust. If the piece you are using is meant to be practical like a knife you can wax the surface. If the piece is more decorativ, than you can add a clear coat to it. It's all a matter of preference. For mine above, I decided to try a clear nail polish. I usually use clear polyurethane, but I wanted to try something else for a change. Once the piece is protected, all that is left is to display it.
Step 6: One Last Point
The piece I made here didn't require any quenching or heat treating because it is a decorative piece. If you choose to make a blade out of cable Damascus one thing to keep in mind is that when quenched, the steel has a tendency to warp in the direction of the cable twist. If you want a functional piece, make it thick, otherwise you might start with a knife and end up with a corkscrew.